SACReg: Scene-Agnostic Coordinate Regression for Visual Localization

Scene coordinates regression (SCR), i.e., predicting 3D coordinates for every pixel of a given image, has recently shown promising potential. However, existing methods remain mostly scene-specific or limited to small scenes and thus hardly scale to realistic datasets. In this paper, we propose a new paradigm where a single generic SCR model is trained once to be then deployed to new test scenes, regardless of their scale and without further finetuning. For a given query image, it collects inputs from off-the-shelf image retrieval techniques and Structure-from-Motion databases: a list of relevant database images with sparse pointwise 2D-3D annotations. The model is based on the transformer architecture and can take a variable number of images and sparse 2D-3D annotations as input. It is trained on a few diverse datasets and significantly outperforms other scene regression approaches on several benchmarks, including scene-specific models, for visual localization. In particular, we set a new state of the art on the Cambridge localization benchmark, even outperforming feature-matching-based approaches

Prevention of wrong way accidents on highways: a human factors approach

TRA2014 - Transport Research Arena, PARIS, FRANCE, 14-/04/2014 - 17/04/2014Every year, on highways, drivers taking wrong way cause accidents. This paper focuses on a behavioral evaluation of two static road signs to prevent wrong way driving. The devices are a light barrier and the standard wrong way signal (B1) on a yellow background (B1Y). Currently, the design or selection process of road signs does not take into any systematic Human Factors criteria. One of the objectives of the research is to identify a design methodology of road signs. Two questions are asked : 1) how an 'impaired driver' reacts when facing signs designed to prevent a wrong way, 2) to define the impact of this type of road sign on attention and behavior of drivers. Dynamic tests are used to evaluate the robustness of both road signs against different risk factors and more specifically, age. The results of tests give a complete evaluation (qualitative and quantitative) of the wrong way road signs and the implication for road sign design and human factors evaluation.Chaque année sur les routes à chaussées séparées des conducteurs s'engageant en contresens provoque des accidents. Ce document traite de l'évaluation comportementale de deux dispositifs statiques pour empêcher les prises à contresens. Les dispositifs sont une barrière de plots lumineux et le panneau sens interdit classique (B1) sur fond jaune (B1J). Actuellement, le processus de conception ou l'évaluation de signalisations ne prend pas en compte les critères des facteurs humains. L'un des objectifs de la recherche est d'identifier une méthodologie de conception de la signalisation routière. Deux questions sont posées : 1) comment une 'conduite diminué' réagit face à une signalisation anti-contresens, 2) Définir l'impact de cette signalisation sur l'attention et le comportement des conducteurs. Les tests dynamiques ont été réalisés pour évaluer la robustesse des nouvelles signalisations routières par rapport à différents facteurs de risque et de la perception du danger. Les résultats des tests donnent une évaluation complète (qualitative et quantitative) des signalisations anti-contresens et les implications pour la conception de signalisation routière ainsi que l'évaluation des facteurs humains

CroCo v2: Improved Cross-view Completion Pre-training for Stereo Matching and Optical Flow

Despite impressive performance for high-level downstream tasks, self-supervised pre-training methods have not yet fully delivered on dense geometric vision tasks such as stereo matching or optical flow. The application of self-supervised concepts, such as instance discrimination or masked image modeling, to geometric tasks is an active area of research. In this work, we build on the recent cross-view completion framework, a variation of masked image modeling that leverages a second view from the same scene which makes it well suited for binocular downstream tasks. The applicability of this concept has so far been limited in at least two ways: (a) by the difficulty of collecting real-world image pairs -- in practice only synthetic data have been used -- and (b) by the lack of generalization of vanilla transformers to dense downstream tasks for which relative position is more meaningful than absolute position. We explore three avenues of improvement. First, we introduce a method to collect suitable real-world image pairs at large scale. Second, we experiment with relative positional embeddings and show that they enable vision transformers to perform substantially better. Third, we scale up vision transformer based cross-completion architectures, which is made possible by the use of large amounts of data. With these improvements, we show for the first time that state-of-the-art results on stereo matching and optical flow can be reached without using any classical task-specific techniques like correlation volume, iterative estimation, image warping or multi-scale reasoning, thus paving the way towards universal vision models.Comment: ICCV 202

Long-Term Safety and Efficacy of Single or Repeated Intra-Articular Injection of Allogeneic Neonatal Mesenchymal Stromal Cells for Managing Pain and Lameness in Moderate to Severe Canine Osteoarthritis Without Anti-inflammatory Pharmacological Support: Pilot Clinical Study

Objective: To explore the long-term safety and efficacy of canine allogeneic mesenchymal stromal cells (MSC) administered intra-articularly as single or repeated injections in appendicular joints of dogs affected by moderate to severe refractory osteoarthritis.Study Design: 22 pet dogs were recruited into a non-randomized, open and monocentric study initially administering one cellular injection. A second injection was offered after 6 months to owners if the first injection did not produce expected results.Materials and Methods: Anti-inflammatory treatment (if prescribed) was discontinued at last one week before the onset of treatment. Each injection consisted of at least 10 million viable neonatal allogeneic mesenchymal stromal cells obtained from fetal adnexa. Medical data was collected from veterinary clinical evaluations of joints up to 6 months post-injection and owner's assessment of their dog's mobility and well-being followed for a further 2 years when possible.Results: Mild, immediate self-limiting inflammatory joint reactions were observed in 5/22 joints after the first injection, and in almost all dogs having a subsequent injection. No other MSC-related adverse medical events were reported, neither during the 6 months follow up visits, nor during the long-term (2-years) safety follow up. Veterinary clinical evaluation showed a significant and durable clinical improvement (up to 6 months) following MSC administration. Eight dogs (11 joints) were re-injected 6 months apart, sustaining clinical benefits up to 1 year. Owner's global satisfaction reached 75% at 2 years post-treatmentConclusion: Our data suggest that a single or repeated intra-articular administration of neonatal MSC in dogs with moderate to severe OA is a safe procedure and confer clinical benefits over a 24-month period. When humoral response against MSC is investigated by flow cytometry, a positive mild and transient signal was detected in only one dog from the studied cohort, this dog having had a positive clinical outcome

Des approches prescriptives aux systèmes de gestion du risque fatigue

The impact of hours of work on employees’ health and safety is a critical issue given the increasing use of abnormal hours of work in a number of industries, services or transports. The prevention of fatigue associated with these hours of work is most often based on regulatory approaches that rule the duty time limitations and minimum rest time. These prescriptive approaches have several caveats, including for employees’ fatigue. This article presents an alternative for managing the risk of fatigue as close as possible to specific work constraints. The general principle of these fatigue risk management systems is presented and illustrated by a few examples. Their main limitations are also discussed

Integrating Aircrew Resources Variability into the Design of Future Cockpit

Cockpit design may have major consequences on future pilot’s tasks. Functions needed to ensure flight safety are shared between pilots and aircraft systems. Today, cockpits are designed considering a theoretical minimum level of crew resources availability although it is widely acknowledged that availability of crew resources may vary from time to time because of aircrew internal state. Therefore, it is crucial to ensure that future cockpits are designed while taking into consideration this variability. This work aims at developing a methodology enabling designer to systematically integrate crew resources availability in the design process. In order to assess the impact of different sources of variability, the principles of the systemic model FRAM is used. The present work is analyzing the impact of crew resources availability on several use cases using FRAM principles. The data are collected by the means of focus group with operational and human factors experts. Some preliminary results are presented and discussed

Stratégies de protection de la performance pour la conception de cockpits résilients (le cas de la fatigue en situation inattendue de résolution de problème)

Résumé confidentielRésumé confidentielPARIS5-Bibliotheque electronique (751069902) / SudocSudocFranceF